The invention concerns a support with a material layer, in particular an information support, wherein the material layer is a colored layer and is introduced onto the support using an ultrasonic sonotrode as well as a method for the production of a support, in particular for the protection of data deposited on an information support, wherein the information is covered with the material layer which bonds firmly to the information and the material layer is destroyed to remove same without damaging the information.
Supports of this kind are for example utilized as information supports, wherein the colored layer is used as a cover for a secret numerical code. WO 97/49499 discloses the use of liquids such as paints as the colored layer which are introduced by means of ultrasonic sonotrodes in a dosed fashion onto the support to thereby create a homogenous cover of the support. A material web which is to be coated is guided over the surface of the ultrasonic sonotrode wherein, with the application of pressurized air and/or with correspondingly running rollers and an appropriate tension of the material web, a defined pressing is produced. DE 3715146A1 discloses the welding or gluing of material webs, in particular packaging material, using ultrasonic technology and ultrasonic sonotrodes with the associated anvil portions being moved towards each other and using an overlay of vibrational motion for processing, such as welding, the material web.
Ultrasonic sonotrodes permit very thin material layers to be introduced onto the information support with very strong bonding thereto without subjecting the information support to high temperatures. The transferred material layer can, if necessary, be kept very thin and be permanently attached to the support. Ultrasonic sonotrodes can achieve a very high production speed and a covering of this kind is safe and economical. The sonotrode produces ultrasonic vibrations of defined area which activate the material layer which is to be introduced onto the information support and intensively bond that layer to the information support. Information which lies underneath the material layer, such as an a numerical code, is covered in a secure and unrecognizable fashion and can only be exposed upon destruction of a material layer, wherein the information, in this case a numerical code, is not thereby damaged for further use.